Conversion of colonoscopy to sigmoidoscopy as a quality indicators

Conversion of requested colonoscopies is a clinically significant phenomenon and whether this impacts upon the measurement of quality indicators, reports the most recent issue of the American Journal of Gastroenterology.

A cecal intubation rate of >90% is a well-accepted quality indicator of colonoscopy and is consequently monitored within endoscopy units.

Endoscopists’ desire to meet this target may mean that incomplete colonoscopies are recorded as flexible sigmoidoscopies.

Dr Sabina Beg and colleagues from the United Kingdom examined whether the conversion of requested colonoscopies is a clinically significant phenomenon and whether this impacts upon the measurement of quality indicators.

The researchers performed a retrospective review of all flexible sigmoidoscopies performed in 2015 at Nottingham University Hospitals, Sheffield Teaching Hospitals, and Cambridge University Hospitals.

Where a colonoscopy was requested but a flexible sigmoidoscopy performed, the patient’s records and endoscopy reports were reviewed to determine whether this conversion was decided before the start of the procedure and documented.

3% of procedures were originally requested as a colonoscopy

American Journal of Gastroenterology

During the 12-month period, 6,839 flexible sigmoidoscopies were performed by 125 endoscopists.

The research team reported that original requests of 149 sigmoidoscopies could not be retrieved and were therefore excluded from this analysis.

Of the 6,690 sigmoidoscopy requests reviewed, 3% of procedures were originally requested as a colonoscopy.

On review of patient records, the team found that 85 conversions were appropriate according to pre-defined criteria.

However, 105 conversions were deemed inappropriate, occurring in patients who had a valid documented indication for colonoscopy and had undergone full bowel preparation.

The researchers noted that the most common reasons cited included poor bowel preparation, technically challenging procedure, at the endoscopist’s discretion based on clinical factors, and obstructing patology.

A clear reason for conversion was not apparent in 11 cases.

During the study period, 21,271 colonoscopies were performed and so conversions represent 0.45% of the total requests.

The researchers found that when inappropriate conversions were included in individuals’ performance data, 15 endoscopists fell to ≤90% target cecal intubation target.

Dr Beg's team comments, "A small, but significant number of colonoscopies are converted to flexible sigmoidoscopies at the time of the procedure."

"This study demonstrates the conversion of colonoscopy to sigmoidoscopy as being a potential limitation of relying on cecal intubation rate alone."

"Endoscopy units should consider monitoring the rate of inappropriate conversions to ensure quality."